<!DOCTYPE html>
<html>
  <head>
    <meta charset="UTF-8">
    <title></title>
  </head>
  <body>
    <div id="test"></div>
    <script src="./js/browser.js"></script>
    <script src="./js/react.js"></script>
    <script src="./js/react-dom.js"></script>
    <script type="text/babel">
      let dom = document.querySelector("#test");
      class Aaa extends React.Component{
        constructor(...args){
          super(...args);
          this.a = 12;
          this.arr = [52,4,5,48,9,7,5];
        }
        render(){
          let ali = this.arr.map(v=><li>{v}</li>)
          return 
          <div>
            <span>{this.a}</span>
            <ul>{ali}</ul>
          </div>
          ;
        }
      }
      ReactDOM.render(<Aaa></Aaa>,dom);
    </script>
  </body>
</html>